Hello! There are many indicators to show a sign that a chemical reaction has occured. These are 3 as followed.
1. An odor is produced.
2. A change in temperature.
3. A color change.
Others can be a formation of a solid or a gas.
Answer:
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Answer:

Explanation:
It is given that, a proton moves at constant velocity, through a region in which there is an electric field and a magnetic field such that,
The electric field is, E = 800 V/m
Magnetic field, B = 0.25 T
We know that the net force in the region of magnetic and electric field is given by Lorentz forces. But here, the proton moves with constant velocity. So, the net force acting on it is 0.
i.e.

Hence, this is the required solution.
Answer:
The frequency increases.
Explanation:
When the Musician draws the slide in the length of the horn gets shorter, which causes a decrease in the wavelength. A decrease in the wave length results in an increase in frequency.
Note:
The diameter of the horn has an effect on frequency, so a wider horn is effectively a long horn - open end correction ( distance between the the antinode and the open end of a pipe).
Frequency also depends on how hard the musician blows the trombone. The musician can change the frequency with the lip pressure being applied.